Mats are used as a platform and/or as a road surface. Mat configurations vary in size and shape. Some mats are discrete units, which when assembled form the platform and/or the road surface. The most common configuration comprises a series of logs attached laterally by cables, bar stock or ropes. FIG. 1 shows such a configuration. The logs 1 are connected by cables, bar stock or ropes 2. A transport cable or rope 3 is provided for positioning the assembled logs.
The discrete unit configuration is popular as it is readily adaptable to many situations. Terrain and work conditions may vary widely [i.e., mud versus rocks and/or soft soil, hills, valleys, short versus long traverses with various widths in the platform or road, etc . . . ]. Therefore, the discrete unit configuration is more adaptable than other configurations, such as the surfacing or the track-way system described in U.S. Pat. No. 4,488,833 issued to Perry, et al., showing a plurality of rectangular planks joined to each other by hinge members so that the system may be stored by folding the planks in an accordion fashion. The discrete unit configuration has an individual, modular-like capability, making it more versatile and more easily changeable to meet the many unique terrain and surface conditions.
In the past, the most desirable material used for constructing discrete unit configuration mats has been wood since it is readily available and is easy to work with. Other materials have been introduced, but, these are more difficult to handle when forming the desired configuration. Durability is also an important consideration. With mats made of wood, the problem of durability becomes especially acute because over time the wood is subject to deterioration due to weather and other environmental conditions. This adverse effect can be somewhat mitigated by specially treating the wood. However, this adds considerably to the cost of fabricating the mats. Additionally, the mats are easily cracked and gouged by the steel tracks of the equipment using them.
Since these mats are often somewhat large in dimension [some averaging up to 40 feet by 10 feet], heavy lifting and moving equipment is typically necessary to transport and then arrange the mat at the site where it is to be used. Also, since construction of the mat at the site where it is to be used is practically impossible, transporting the mat to the site is a factor which must be addressed.
Prior discrete mat inventions require manual labor to some extent when they are being moved and arranged. Typically, workers must physically attach a cable or other pulling mechanism from the mat to the moving equipment, creating an unsafe working condition. The attached cable may break causing a lifted mat to fall, damaging or possibly destroying the mat and anything in its path.
It would be desirable, therefore, to have a mat which possesses a number of capabilities, one of which is that each mat should be readily transportable in a safe manner from the fabrication site to the use site, and then easily and safely arranged in assembly with other mats to form the completed platform and/or road surface. Also, the mat must be made of durable material, capable of withstanding the heavy loads required by its use as a platform and/or road surface. It should also be capable of being made of material which is not significantly impacted by environmental conditions and is relatively inexpensive to fabricate.